bcrump's blog

 Because of threatening weather offshore we decided to leave the estuary a little early on the morning of the 28^th.  We first went 15 miles offshore to dump our holding tank, and then begin our series of CTD casts down the one hundred meter isobath. The weather remained nice and we even had a following current down the coast causing us to complete our survey very quickly.

At 0600 we replaced the long pump hose with a much shorter one to make it easier to prime the pump and get the water flowing.  David Needham set up a primary production measurement at 0700, and the water sampling team collected DNA and RNA samples and measured bacterial production.  Water sampling for methane, CDOM, and nutrients continued until 1200.  Then at 1500 we got underway and steamed

We continued to collect samples at the RM-17 station hourly until 1000, and then pulled the anchor and went to the dock at the Job Corp campus on Tongue Point. Colleen Durkin and Sara Bender disembarked with their equipment, and undergraduate intern Lindsey Longway came aboard. We then steamed upriver to the Beaver Army dock at river mile 53, conducted a CTD cast, and then tied up at about 1800. We attached the end of the pump hose to a pole and strapped to the port side of the ship so that the hose end was positioned at 1m depth.

At around noon we crossed back into the estuary, conducted a CTD cast at SATURN-03, and continued up the estuary to an anchor station just off Tongue Point on the south bank of the channel at river mile 17 (RM-17). We began hourly CTD casts at 1400 and collected water for nutrients, POC/N, SPM, and DOC each hour beginning at 1200.

At 0900 we collected a water sample from a bottom depth for a full suite of chemistry and nucleic acid analysis. This sample was fresh water, and it served as the first of five bottom-water samples that spanned the flood tide ETM particle resuspension event. The others were collected at 1200, 1300, 1500, and 1600. Also, a surface water sample was collected at 1300. At 1900 we steamed across the bar and out to the coastal ocean to empty the holding tank and dispose of garbage. We spent the night off shore.

Currents during strong ebb tide were too much for our sampling system, and we were forced to suspend sampling for several hours in the early morning.  Misty Blakely sampled every hour for chlorophyll, nutrients, and TDN/P.  We sampled for a full suite of chemistry and nucleic acids at 0200 (s,b), 0600 (s,m,b), 1100 (b), 1120 (s,m,b), 1200 (b), 1430 (b,m,s), and 1630 (b,m,s).

The plume feature tracking exercise continued until 1100.  We collected water samples for the micro baseline sample set at four depths at stations PLT-7 (cast 85, 0100), PLT-13 (cast 91, 0600), and PLT-18 (cast 96, 1100).  We also collected water at PLT-13 for a primary production measurement and for Florian Moeller’s ammonia oxidation experiments. 

In the morning we docked at the Job Corp docks on the east side of Tongue Point.  One of the crew on the New Horizon had attended school at Tongue Point, and with that connection we were able to secure permission to dock.